Effect of screw spacing on axial strength of cold-formed steel built- up box sections-numerical investigation and parametric study (original) (raw)
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IOP Conference Series: Materials Science and Engineering
The use of cold-formed steel (CFS) as a frame in a single-story structure building system has been widely applied. However, the use of cold-formed steel for multi-story buildings is still constrained in the structure system, especially column. In the conventional structure, columns used in large dimension, height, h> 150 mm and thickness, t> 1.2 mm which makes the construction cost expensive. An innovation of cold-formed steel combine profile into one compression member unit is very interesting to study, furthermore, previous research provides information on a variety of cold-formed steel behaviors with small dimensions of height, h <150 mm and thickness, t <1mm, which can be developed into columns with greater strength. There have been a lot of research on behavior on cold-formed steel, but the study on screw optimization especially on combined profile to become compression member still need to develop. From the compression test on double profile back to back and flange to flange length, l = 300 mm and screw distance variation, 25 to 150 mm with 50 mm intervals, indicating a response similarity at screw spacing 25 mm, 50 mm and 75 mm, while the screw distance 100 mm, 125 mm and 150 mm experienced backline capacity.
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Effect of Screw on the Axial Performance of Cold-Formed Steel
International Journal of GEOMATE, 2022
Along with the development of the construction world in Indonesia, the use of cold-formed steel (CFS) as a construction material is also increasing. The connection is an important element that must be considered in this type of material. Structural elements that are joined experience stress concentration around the hole resulting in a change of the behavior of structure that becomes more complex. To predict the failure mode of the connection section, this study conducted an experimental test to study the capacity of cold-formed steel against tensile loads. The test specimens used in this study are canal type, which is usually used as material construction, with three different configurations of screw positions. The effect of the screw will be compared with an original model without a screw. In addition, numerical simulation by ABAQUS Student Edition and analytical studies by SNI 7971:2013 which referred to AS/NZS 4600:2005 have been conducted to investigate the axial capacity of the CFS element. From the experimental results, the main failure modes for all types of screw connections are categorized by tilting and pull-out failure. Increasing space between screws will also increase the maximum load by 6.67% and 10.81% for connection with three and four screws, respectively. In addition, the specimens with one and four screw connections have an average extension which was 300% larger than that of without screw.
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